Japanese Language Stack Exchange is a question and answer site for students, teachers, and linguists wanting to discuss the finer points of the Japanese language. It's 100% free, no registration required.

2 Answers
2

誰 by itself does not mean 'who'. Nor does も always mean 'also'. Words like 誰 are called indeterminates, and are more essential than wh-words (It can be a part of the meaning of a wh-word; Not wh-word itself). 誰 only means 'some variable (something that does not have a fixed reference) that ranges over people'. Depending on what particle it is used with, it would be translated into different words in English: